There's no Exchange tab on the shop.. I saw videos where it used to be there.

How can I do it now?

Ok, nevermind.

I fixed.. The tab wasn't showing (no space on the screen I guess) so I put the "commands" tab set to false.. 
Now it shows ;)

you may be able to go into your rust setting and change the UI scale to something like 0.8 or smaller.

Ive blown a few minds with that.